A Conceptual Scheme for Cyber-Physical Systems Based Energy Management in Building Structures Peng Zhao, M. Godoy Simões, Siddharth Suryanarayanan The Center for Advanced Control of Energy and Power Systems (ACEPS), Colorado School of Mines pzhao@mines.edu Abstract-Concerns about energy efficiency and carbon footprints are becoming more significant in the power industry and public policy, as evidenced by the concerted shift to renewable energy sources and energy conservation paradigms. One of the largest consumers of energy in the US is the residential and commercial buildings sector. This paper explores a conceptual framework of a cyber-physical system (CPS) for energy management in such structures, viz. a Cyber-enabled Efficient Building Energy Management System (CEBEMS), aimed at attaining some level of energy self-sufficiency. I. INTRODUCTION An accepted definition of a cyber-physical System (CPS) is one where “physical and software components are deeply intertwined, each operating on different spatial and temporal scales, exhibiting multiple and distinct behavioral modalities, and interacting with each other in a myriad of ways that change with context” [1]. The scope of this paper pertains to the definition of a conceptual framework of a CPS for efficient energy management in building structures. A CPS-enabled energy management system in building structures is concerned with the sensing and control of energy flows. Modern buildings exhibit a tight integration of sensing, computation, and actuation within multiple physical domains [2]. For example, larger buildings usually contain a sensor network, with a variety of sensors that measure electric power flow, temperature, relative humidity, carbon monoxide and CO 2 levels [2]. They control the operation of the chiller and heating systems, and may have actuators to control the air- flow into and through the building, or building access. The energy management and control system uses the sensor measurements and determines actuation; the control of which can be of a hierarchical or distributed nature. The full potential to achieve efficient energy management in building structures requires information on the thermal behavior of the building, accurate predictions of weather and building use, input from spot energy markets, equipment efficiency characteristics, and possibly access to distributed generation (DG), energy storage, smart grid technology and an evolved communication infrastructure. The efficient management of energy in structures thus presents a ripe area for the exploration of deploying cyber resources. Building operating systems such as heating, ventilating and air conditioning (HVAC) system, lighting, vertical transportation, other electrical loads depend on energy from a variety of sources such as electricity, oil, and gas, for providing acceptable levels of security and comfort to the user [3]. However, over 40% of energy consumed in residential and commercial buildings is associated with low efficiency heating and cooling loads; a behavior that has been enabled by the traditionally low-cost of fuels such as natural gas, propane, and fuel oil used in heating [4, 5]. As energy prices soar concomitantly with the needs of reducing dependence on fossil fuels usage and curbing carbon footprints, Building Energy Management Systems (BEMS) present an important avenue for the pursuit of end use energy efficiency. A possible solution includes incorporating local DG and renewable energy sources (RES) to offset the consumption of heating fuels and electricity from the grid. The control and use of a BEMS may present an ideal avenue for deploying CPS that may boost the overall efficiency. In the face of looming energy and environmental challenges there is increasing interest to both retrofit existing and build new building structures with low- and zero-energy performance characteristics [6]. To achieve maximum energy efficiency in a building structure, a holistic perspective that considers both thermal and electrical energy systems in the presence of sensors is needed to anticipate changes in the environment and respond dynamically while maintaining comfort and efficiency [7]. Such a perspective would also consider the implications of distributed controls, DG, heat recovery techniques, and communications infrastructure [7]. A cyber-enabled distributed control methodology using multi- agent systems (MAS) for efficient management of both electrical and thermal energy systems is proposed here as a tool for realizing maximum efficiency energy management, which would provide heating, cooling and electrical services Efficient electric energy management within cyber-enabled buildings and interconnected operations with the electric grid are integral aspects of the philosophy of energy efficient building design [8, 9]. This may include control of DG sources, energy storage mechanisms and a user-friendly interface to make the structure customer-driven from the perspective of the electricity markets. At the interface between the electricity grid—the major provider of external energy—and the end user is a set of devices including a smart interface device (usually, a power electronic device with advanced capabilities) and a portal for exchange of information with the provider (i.e., a smart meter) [10-14]. Some of the functionalities of the smart meter include two- way communications between the end user and the utility